Process of manufacturing a shaving tool



Dec. 5, 1939. .1. BRUECKER 2,182,067

PROCESS OF MANUFACTURING A SHAVING TOOL Original Filed May 20, 1937 5Sheets-Sheet l @x @3 @w @A Mmm 0% @3% QW@ M@ WQ@ @Mx f3@ @Q3/@W65 J.BRUECKER PROCESS" oF MANUFACTURING A sHAvING TooL Dec. 5, 1939.

Original F'iled May 20, 1937 3 Sheets-Sheet 2- 35H Bmx/5069 I 53M? aM/mYZQMM @bun/m Dec. 5, 1939. J. BRUECKER PROCESS OF MANUFACTURING ASHAVING TOOL Sheets-Sheet 3 Original Filed May 20, 1937 v PatentedDem-5, 1939 l UNITED] STATES PROCESS F A SHAVING John Bruecker, Chicago,lll.

Original applicaticnlMay l20, 1937, Serial No.

Divided and this application February 8, 1938, Serial No. 189,573

11 Claims'. (Cl. i6- 104) This application is a division of myvapplication l Serial No. 143,754, iiled May 20, 1937, and is acontinuation in part of my application Serial No. 98,541, led August 29,1936, von which Patent No. 2,081,694, was granted May 25, 1937, for whatis commonly known as a dry shaver. The present invention relates to aprocess of 'manufacturing a shaving tool such as a dry shaver and hasparticular reference to the manufacture of the perforated shearing bladefor what in commercial practice is termed'the comb.

An object of my invention is to provide improved methods' ofmanufacturing shearing blades suitable for use in a dry shaver, wherebyl5 4to eect economies in the cost of manufacture and to provide a moreelcient and satisfactory shearing blade for the purpose intended.

Other objects and attendant advantages will be appreciated by thoseskilled in this art as the invention becomes better understood byreference to the following description when accompanied by the followingdrawings, in which- Figure 1 is a longitudinal section through the'cutting head end of a shaver made in accordance with my invention;

Fig. 2 is a section taken substantially on the vsection line 2-42 ofFigure l;

Fig. 3 is a plan view of one embodiment of the thin shearing blade whichforms the cutting head, one end ofthe blade being broken away;

Fig. 4 is an enlarged plan or face view of the perforated portion ofsaid shearing blade;

Figs. 5 and 6 are detail sectional views showing the manner in which theslots are formed in the central portion of said shearing blade; y

Figs. 7,` 8, 9 and l0 are enlarged plan views of the face of a shearingblade in connection with different methods of making the same accordingto my invention; Figs. ll, l2, 13 and 14 are vertical sectionscorresponding with Figs. 7, 8, 9 and 10, respectively,

Fig. 17. is a vsomewhat diagrammatic view I showing a shearing blade ofthe kindillustrated in Fig. 10 supported in an operative position in theshaver, the radius being larger than that of the lapping tool; I

Fig. 18 is an enlarged detail section crosswise through one of theperforations of the shearing blade in its operative position shown inFig. 17, as for example, taken on. the section line I8---I8 of Fig. 10;y i I 5 Fig. 19 is a plan view of the face 'of a shearing blade of amodified form, embodying my in'ven'- tion;

Fig. 20 is a somewhat diagrammatic view illus-J trating a step in theoperation of forming the 10 blade shown `in Fig. 19;

Fig. 21 is an enlarged detail plan view of a perforated portion of theblade shown in Fig. 19;

Fig. 22 is a section taken on the section lline 22-22 of Fig. 21, and 15Figs. 23 and 24,illustrate`addltional forms of punching operationsl inthe manufacture of a cutting head according to my invention.

' convenient. manipulation, which preferably but not necessarilyvincludes an electric motor or the equivalent vfor operating the cutter.In the present embodiment I have omitted the motor end of theunit andhave shown only the cutting 25 head end. The construction shown ismerely for purpose of illustrating the principles of my infvention. X

Referring to Figs. 1 and 2, the cutting head designated generally by thereference numeral 24 30 and in commercial practice called the comb, isof extremely thin exible material, such for example, as a strip ofspring steel of approximately .003",in thickness. In the preferred formthe lcomb has closely positioned perforations or hair- 35 receivingopenings 25 throughout a medial area 2B. 'I'he comb is normally fiat,asshown in Fig. 3. ByA flexing the comb medially to the semi-cylindricalform shown in Figure 1, the nat end portions 21. may be inserted throughnar'row sloto like openings 28 in the housing tothe operative positionhere shown. In this position, the marginal portions 29 along thelongitudinal edges of the comb seat against semi-circular shoulders 30formed on a suitable support or bracket hav- 5 ing end walls 3| and`side walls 32. Suitable means, such as spring holding elements 33,enter openings 34 in the comb and exert a downward pull to hold themarginal portions 29 iirmly seated against the stationary shoulders 30and with the perforated portion in the flexed or semicylindrical shapeshown. The bracket is xed within' a suitable housing designatedgenerally by 35. Each spring element 33 is part of a coil l Vspring 36carried on a post 31 extending between 55 opposite walls of the housing35, the spring elements being constantly Vurged inwardly and downwardlyto pull the comb down to its working position. Suitable means such as akey not shown here but disclosed in my prior application may be providedfor spreading the spring elements 33 and withdrawing them from the combso that the latter is free to be removed through the openings 28. Itwill be apparent that the user may grasp the projecting comb between thefingers and remove it bodily. This is desired for the purpose ofreplacing the comb orfor changing blades and also for giving access tothe cutter for inspection and replacement. The comb may be replaced byrepeating the operation, the key being removed or withdrawn after thecomb is in the working position, thereby permitting the spring elementsto engage the. end portions oi the comb to hold the comb firmly againstthe seats 3B. In the commercial practice of my invention the comb isheld in arcuate form by means other than disclosed in the presentapplication, the commercial means being the subject matter oi a separateapplication.

The cutter 38, preferably of steel or a suitable alloy, is in the formof a' thin at blade and extends lengthwise from end to end of thecutting head as shown in Fig. 2. The cutter is carried by a rock-bar 39mounted to oscillate on suitable bearings di), in .this instance carriedbythe end walls of the bracket. In the preferred form, the center aboutwhich the rock-bar oscillates is concentricvwith the semi-cylindricalperforated portion of the cutting head. The rock-bar is suitably slottedor shaped to receive the cutter so that the latter is free to movevbodily outwardly under centrifugal force when the rock-bar is oscillatedat 'a high speed, or to move outwardly under the influence of springpressure such as imposed by a suitable spring di., or by the inuence ofboth centrifugal force and spring pressure, 'as here employed. This isto maintain the cutting edge of the cutter in intimate shearingengagement with the inner face of the comb from end to .end of thecutter. The.- cutter is oscillated at a comparatively high speed bysuit- This may be done in many tween parallel plates 45 fixed to therock-bar. By

this means the cutter will b'e oscillated ata high speed,'in thisinstance; through an arc indicated by the dotted line positions of thecutter, Fig.. 1. The pressure of the cutter against the inner face ofthe comb will be uniformly distributed from end to end of the cutter,and the cutting'edge will be constantly urged against the extremely thincomb so as toprovide intimate shearing engagement between the edge ofthe cutter and the numerous cutting edges formed by the` perforations inthe comb. In the form here shown the cutter is mounted so that it isfree to have a tilting movement upon and with respect to the priorapplication; but it will be manifest thaty thisY pronounced tiltingaction is not essential.

In the commercial practice of my invention the cutter is mounted in aradial position with respect to the rock-bar and has uficielll Play.

therein tol permit of the desired bodily movement under centrifugalaction or spring pressure, or both, as hereinabove described.

The hair-receiving openings are confined to the zone 26 above mentionedwhich is shorter in length than the travel of the cutter at its outerend. Thus the cutter atfeach end of its stroke comes to rest at animperforate area @l and thereby avoids any danger of uncut hairs beingcaught between the cutter and the comb at this stage of `the operation.I prefer to employ a series of openings 48 in the comb just beyond eachimperforate area 41 for the discharge respect to the slots of thecontiguous series. The

slots are formed by placing the comb forming strip between a pair ofdies, one of which embodies a plurality of ribs corresponding in numberand design to the slots, and the otherv of which embodies a plurality ofrecesses for receiving the ribs of what may be termed the male die. Whenthe dies are brought together with the comb forming strip therebetween,the ribs ci the male'die deiiect vthe metal of the strip so that thelatter has indentations 9 on one side thereof and projections 5t on theother side. The ribs on the male die are greater in height than thestrip is thick with the result that the indentations in the one side ofthe strip, that is, the skim-engaging face, are of greaterdepth than thestrip. After the strip has been subjected to the action of the dies, theprojections 5@ on the inner' face of the strip are ground oil orreduced, with the result that the slots 25, referred to above ashair-receiving openings, are formed. Becausev of the specific manner inwhich the slots areiormed, the comb has on the outer face thereof aplurality of series of cavities or indentations de, and embodies on itsinner face cutting edges 5i. The latter denne the slots and are ush withthe inner face of the comb.

When the comb is moved over the skin for shav-` ing or hair depilationpurposes, `the skin works its way into the cavities and the hairs whenthey encounter the slots, snap or work their way through the slots.Because of the cavities and the manner in which they operate to receivethe skin, the cutting edges 5I are aligned with the hairs at the pointsat which they protrude from the skin. As a result .of this, the bladetype cutter 38 whenit is oscillated within the comb as abovedescribed,'eects an extremely close cutting of the hairs. ".l'helcavities '49 are dished and serve to direct the hair through 'the slots.The

slots are the same in length, as shown in Fig. 3,

' and each slot is placed from the adjoining slots of its series adistance slightly less than the slots length. As a result of this,andbecause the slots of every other series are staggered vwith respect tothe slots of alternate series, all of the hairs" encountered by the combduring each sweep of the head in ponnection withv a shaving or hairdepilation 'operation are encountered by-the slots.

and are subjected to the shearing action of the cutter against thecutting edges at Athe inner face of the comb.

' shearing blade. InFigs. 8 and 12 a second set of male and female dies56 and 51, respectively, form the indentations 50 and projections 59 onthe transversely perforated strip 55. In Figs. 9 and 13a set of male andfemale dies 00 and 6I, respectively, form the indentations .and projec-'tions and also slit or perforate the metal strip 52 in a singlepunching or stamping operation. x.

In Figs. 10 and 14 a second set of male! and female dies I3 and 6I,respectively, further perforate the indented and slitted parts of thestrip 02 to give greater width to the slots. All of the foregoingoperations are formed with the strip fiat.

My invention contemplates finishing the inner face of the comb in suchmanner as to insure the provision of cutting edges either ush with suchinner face or spaced slightly inwardly from such face. thereby insuringmost efli'cient shearing action by conjoint use of the cutter. 'I'his isaccomplished preferably by flexing the perforated portion of the comb orstrip to a curvature approximately the same as it occupies `when inoperative position and lapping the inner face by means of a lapping toolof ,approximately the same diameter. manufacture is illustrated in Fig.in which one of the comb strips here designated 65 is held on an annularlapping bar or arbor 06 in substantially the same shape and condition aswhen itis in operating position in a shaver. means may be employed lforthis purpose, and I have here shown a spacer 61 connecting the flatsides of the strip, holding them in approximately parallel relation.` Bysuitable motion of the lapping'bar the projections left on the face ofthe strip asta consequence of the punching or forming operation will beremoved or reduced by abrasion, leaving a smooth, mirror-,like innerface. Preferably a force is applied downwardly on the spacer 61 eitherby spring means or a' weight or suitable. pressure-applying means, sothat the perforated portion of' the strip will be held down against therotating arbor with sub- 50 stantially the same pressure as applied bythe spring elements 33 when holding the strip in operative position in ashaver. Thus I am able to obtain a very ne degree of precision in thesharpness of the shearing edges at the face of the strip and to locatethese edges precisely in the arcuate plane along which the shearing edgeof the cutter travels, In'other words, the cutting edges' at the innerend of the perforations will lie in a true arc coincident to the arc oftravel of the. oscillating cutter, thus giving a very eflicient cuttingaction. By making the perforations in the form o f slots) and arrangingthese at an angle to the plane of travel of the cutter,

a iine shearing' action. is obtained. By making 'the lapping arborslightly smaller in diameter so that the curvature of the perforatedportion of the strip is slightly less than that which it occupiesl inoperative position, the opposed cutting edges at the face of the stripwill be projected slightly inwardlyfrom the inner face. of the .stripwhen the latter is expanded or opened to its operative," position, thusfurther insuring sharp I' cutting action. Another phase of my inventionin this respect'is to expand or open the strip 85 toa wider `diameter'as shown in Fig. 17, in

This step in the operation of,

Suitable which case the semi-circular shoulders and the side walls B9 ofthe bracket or the equivalent on which the strip is supported in theshaver, are shaped to provide for this larger diameter.

Under this condition the opposed shearing edges. -10 will be projectedslightly inwardly in the manner illustrated in Fig. 18. This is due tostressing the metal byI reason of deection from the shape in which theseedges were iinished, the -cieiiected areas being diagrammatlcallyillustrated by the dotted lines in Fig. 10. Contrasted to this, Fig. 16shows the opposed cutting edges 1I of the finished strip 65 in thenormal condition in `which they are finished, that is, flush with theinner face. VWhen the strip is removed from the lapping fixture or fromits operative position in jecting material being accomplished withoutdisturbing the temper of the spring steel strip. Instead of entirelyremoving the projecting m'aterial, this operationv may be carried on.only suflciently to reduce the projection, thus leaving a series ofsmooth iinished surfaces in an arcuate plane slightly spaced from theface proper ofthe strip. This form. of my invention may be usedparticularly where the perforations are quite close together, and insuch staggered relation as to insure continuousbearing contact for thecutter, thus reducing friction between the oscillating cutter and thecomb.

In practice I have made the width of the slots from .009" to .012, and alength of approximate-v ly 11; of an inch. using a strip of spring steelof .003". These dimensions are merely for purpose of illustration. y

.Myinvention also contemplates a comb having the characteristicsdisclosed in Figs. 19 to 22, inclusive. Here the strip of extremely thinmetal designated by 12 is of somewhat different proportions from thatshown in Fig. 3. it being employed in a commercial form of my invention.Insteadof using elongated slots, I prefer an' nular perforations 13closely positioned and arranged in rows longitudinallyand transversely.

'The longitudinal rows indicated by AA are inclin'edwith respect to theendedges 14, and the transverse rows indicated by BB are inclined Aalsowith respect to said edges. staggered relation of the holes, the cuttingedge of the cutter moving across the inner face of the strip iseffective successively on the short lengths of hairL projecting throughthese openings, as a result of which thecutting resistances as well asthe wear on the cutting edge is more evenly distributed. In'this formthere is also Vprovided an imperforate area I15 for the purpose abovedescribed and elongated hair-discharge openingsA By reason of thisscribed above with reference to Fig. 15, thus re-A moving any b urrs orprojecting metal andA providing accurate shearing edges and a smoothsurface on the inner face of the strip. Instead of depressingor'displacing any of the metal ofthe 'strip in this punching operation,I here form merelyannular throughfopenings and in this 'way Iam able tolocate the openings closer together without weakening the metalstructure. The openings at the youter face are then beveled or roundedat the corners as at 19 by separate means such, for example, as by anabrasive buing tool while the strip is heldV on a suitable stationaryxture 8|, as shown in Fig. 20. The tool 80 is shown being rotated in aclockwise direction and moved transversely to the right across theshearing zone, thus reducing the corner edges to a greater degree at theside toward the left. Reversal of this operation similarly reduces thecorner edges at the side toward the left. This gives a somewhatelongated cavity or mouth at the entrance side of each opening as shownin Figs. 21 and 22, which facilitates entrance of the hair. `I may,however, employ die elements such asv 82 and A83 as shown Fig. 24 forperforating the strip andv indenting the outer corners by deiiection ofthe metal in a single stroke of the moving dieelement. This form of diemay also be used in making perforations in the form of slots.

My invention contemplates new and improved results in shavers of thistype, particularly by reason of the provision of annular perforationsarranged close together in a shearing area and providing maximum openarea with maximum strength and maximum length of shearing edges. Inactual practice with a comb of .003" thickness,

I employ perforations of approximately .025"l diameter and space theholes approximately .040" from center to center with respect to eachother. This gives an open area of approximately 35% of the shearing areaof the comb and gives annular cutting edges of considerable length. Thisconstruction also allows a comparatively large body of metal to insurestrength throughout this area. In using a comb of .004 thickness, theperforations would be of slightly larger diameter, and when the comb isof .002" thickness, the openings should be of slightly less diameter.With my invention the hairs enter -the perforations in all directions ofmovement of the comb, but their entrance is facilitated by the cavities'i9 when the comb is worked back and forth in a transverse plane. Byreason of the relatively large open area and the closeness with whichthe cutting edges are brought to the skin without irritation, I am ableto provide closer and more emcient shaving than is possible with priorshavers of this general class.

The inventionis not to be understood as restricted to the details setforth, nor to the embodiments shown, since these may be modified withinthe scope of the appended claims, without departing from the spiritandscope ofthe invention, in which- I claim:

1. The method of making a comb for a shaver l of the characterdescribedcomprising punching perforations in a strip of extremely thinspring metal, and lapping the cutting side of the perforated portionwhile said Yportion is Vflexed in an arc approximating thatl which itoccupies in cooperation with a cutter.

. 2. The 'method of making a comb for a shaver of the characterdescribed comprising perforating a strip of extremely thin spring metalby a punching operationafrom the face side to provide hair-receivingopenings, iiexing the strip to an arcuate form throughout said perforatearea 4 with the cutting side innermost and approximating the arc whichit occupies in cooperation with a cutter, 4and lapping the inner side ofthe strip while it is confined in said arcuate form.

3. 'Ihe method of making a comb as set forth in claim 2, in which thelapping tool is cylindrical and ofA a diameter approximately the same asthe curvature of said cutting side when in operative position in ashaver, and the comb is drawn around the periphery of said lapping tooland the latter is rotated to provide lapped cutting edges in the arcuateplane of the inner side of the comb.

4. The method of making a comb of the char# acter described consistingin forming comparatively small localized depressions in one side of astrip of extremely thin spring metal, removing the projecting metal atthe opposite side ofthe strip sufficiently to provide an opening at the.

base of each depression to serve as a hair-receiving opening, andlapping the inner edges of said hair-receiving openings while the stripis held in an arcuate form corresponding approximately with that whichthe strip occupies in Working position on a shaver.

5. The method of making a comb for a shaver, including the step ofproviding hair-receiving apertures in a thin strip of metal, the step offlexing said apertured portion of the strip to approximately thatcurvature which it will have when placed in operative position in ashaver, and lapping the edges of the apertures on the concave side whilethe strip is held in said exed condition.

in the medial portion of a thin strip of metal, the step o f flexingsaid medial portion so that the side opposite from that first mentionedis of a curvature approximately that which said medial portion will havewhen placed in operative position in a shaver, and lapping the concaveface of said medial portion while it occupies said curvature, whereby toproduce a smooth arcuate surface and cutting edges at the inner end ofthe openings accurately located in said arcuate plane.

7. The method of mamng 'a comb for a shaver, including the step ofpunching hair-receiving openings in a strip of thin spring steel, thestep of flexing the'strip to approximately that curvature which thestrip will have when placed in operative position in a shaver, and thestep of lap,- ping the concave face of the exed strip by means of a toolofapproximately the curvature rst .mentioned l8. The method as set forth-in claim 7, including the step of applying an abrasion tool to theouter face of the perforated portion of the strip to reduce the corneredges at the entrance end of said openings. l

9. 'Ihe method as set forth in claim '7, including the step ofapplying-.a buiiing tool to the outer face of theperforated portion ofthe strip g to reduce the corner edges at the entrance end of saidopenings, and of working saidr bumng tool 'iiexinga the strip toapproximately that .curva-l ture which the strip will have when placedin operative position in a shaver, and the step of reducing saidprojecting portions at the' oppo- 6. The method of making a comb for ashaver, p including the step of punching throughopenings gies-:,007 v 5site side by an abrasion tool and thereby formmost and approximating thearc which it occuing sharp cutting edges at the inner end o! the pies incooperation with a cutter, and lapping openings. the inner side of theperforated area of the strip 11. The method of making a comb fora hairwhile it is in said arcuate form, the lapping tool 5 cutting devicecomprising the steps o! pertorat-- being cylindrical and of a diameterapproxi; 5

ing a strip of thin sheet metal by punching from mately the same as thecurvature ofsaid cutthe face side to provide hair receiving openihgs.ting side o! the comb when it is in operative pobending the strip to anarcuate form throughout sition in the liiitir cutting device.

said perforated area with thecutting-side inner- -JOHN BRUECm.

